NSUInteger count = 0;
NSString *content =
@"[//face[//face[//face[//face[//face[//face[//face[//face[//face";
NSString * string2 = @"[//face";
if(content.length > string2.length || content.length == string2.length){
for (int i = 0; i < content.length - string2.length + 1; i++) {
if ([[content substringWithRange:NSMakeRange(i,string2.length)]isEqualToString:string2]) {
count++; }
}
}